多种对图像加噪声的算法，椒盐噪声，高斯噪声。由于MATLAB自身高斯噪声函数有已经归一化问题，可能结果和自己预想不一样，所以一般都自己来加。-A variety of image plus noise algorithms, salt and pepper noise, Gaussian noise. Gaussian noise as a result of their own MATLAB functions have been normalized problem, possible ou